JPH06102918A - Method for generating cutting route - Google Patents

Abstract

PURPOSE:To automatically generate the cutting route of the minimum number of paths, which corresponds to the machining allowance of cutting by automatically generating the cutting route obtained by offsetting a part which is offset- worked in a work shape based on inputted material shape data, work shape data, cutting method data and offset working data. CONSTITUTION:An input control part 1 stores offset work data DD on the range of a part which cannot be cut by one path, a cutting direction and a cutting condition in an offset working storage part 7. An offset cutting route generation part 8 generates an offset cutting route based on material shape data FR, work shape data FW, cutting method data DP and offset working data DD, which are read from a material shape data storage part 2, a work shape data storage part 3, a cutting method data storage part 4 and an offset working data storage part 7, and stores it in a cutting route storage part 6. On the other hand, a final cutting route generation part 9 generates a final cutting route RF from work shape data FW and cutting method data DP in the work shape data storage part 3 and the cutting method data storage part 4, and stores it in the storage part 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for generating a cutting path in a machining cycle for a numerically controlled lathe.

[0002]

2. Description of the Related Art A method for automatically generating a cutting path from a material shape to a work shape by inputting material shape data, work shape data and cutting method data such as cutting conditions and used tools has been developed and widely used. There is. FIG. 8 is a block diagram showing an example of a function that realizes a conventional cutting path generation method. The input control unit 1 displays a guide on a CRT and the material shape data F input from a keyboard.
R, the work shape data FW, and the cutting method data DP are stored in the material shape data storage unit 2, the work shape data storage unit 3, and the cutting method data storage unit 4. The cutting path generation unit 5 reads the material shape data F read from the storage units 2, 3, and 4.
The cutting path RC is generated based on R, the work shape data FW, and the cutting method data DP, and is stored in the cutting path storage unit 6. For example, in the material shape indicated by aghijklf and the work shape indicated by abcdef in FIG. 9, the number 1 →
A cutting path for cutting is generated in the order of 7.

[0003]

In the case of a material shape in which the machining allowance, which is often seen in casting materials and the like, is uniform and small with respect to the work shape, the machining efficiency is improved if the cutting along the work shape can be completed in one pass. be able to. In the example shown in FIG. 9, when the def portion is attempted to be cut in one pass, the cutting load becomes excessive and cutting cannot be performed in one pass.
The d portion can be cut in one pass. However, in the conventional cutting path generation method, since the cutting paths numbered 1 to 7 are generated as described above, it is necessary to perform laborious work such as inefficient machining or creating a program for each machining step. There was a problem. The present invention has been made under the above circumstances, and an object of the present invention is to provide a cutting path generation method capable of automatically generating a cutting path having a minimum number of passes according to a machining allowance. It is in.

[0004]

The present invention relates to a cutting path generation method in a machining cycle for a numerically controlled lathe, and the above object of the present invention is to input material shape data, work shape data, cutting method data. And, based on the offset machining data, a cutting path that is offset for a portion of the work shape to be offset-processed is automatically generated, and a cutting path along the work shape is automatically generated based on the work shape data and cutting method data. It is achieved by

[0005]

According to the present invention, an offset cutting path is automatically generated for a portion that cannot be cut by the cutting path by one pass based on the work shape and the material shape, and then the cutting path for cutting by one pass is created. Since it is automatically generated, it is possible to set the cutting path with the minimum number of passes according to the cutting allowance.

[0006]

1 is a block diagram showing an example of a function for realizing a cutting path generating method according to the present invention in correspondence with FIG. 8. The same components are designated by the same reference numerals and the description thereof will be omitted. The input control unit 1 causes the offset machining data storage unit 7 to store the offset machining data DD such as the range of the portion that cannot be cut in one pass, the cutting direction, and the cutting conditions, which are input from the keyboard. The offset cutting path generation unit 8 includes each storage unit 2,
An offset cutting path RO is generated based on the material shape data FR, the work shape data FW, the cutting method data DP, and the offset machining data DD read from 3, 4, and 7, and is stored in the cutting path storage unit 6. On the other hand, the final cutting path generation unit 9 generates the final cutting path RF based on the work shape data FW and the cutting method data DP read from the work shape data storage unit 3 and the cutting method data storage unit 4 to generate the cutting path storage unit 6 To memorize.

FIG. 2 is a flow chart for explaining the cutting path generating method of the present invention. For example, aghijkl in FIG.
In the case of the material shape indicated by f and the work shape indicated by abcdef, the cutting load is excessive in the def portion when the cutting is performed in one pass (the mesh line portion in the figure), so the operator de
It is determined that the f portion is to be offset-machined, and the cutting amount T and the feed amount F that reduce the cutting load are determined as shown in FIG. The operator is the data of the material shape aghijklf,
The data of the work shape abcdef, the cutting method data, the offset processing range def, the cutting direction f → e → d, and the offset processing data such as the cutting amount T and the feed amount F which are the cutting conditions are input from the keyboard (step S1). .

The offset cutting path generator 8 determines whether or not the offset machining process remains (step S
2) In this example, since offset processing remains, an offset line is set first. That is, the intersection point j between the normal line from the point d and the material shape is obtained, and the point p returned by the cutting amount T in the direction from the point j to the point d is obtained. Def is offset to the material shape side with the distance between point p and point d as the offset amount, and the offset line nop is set (step S
3). Next, the intersection is calculated (step S
4) It is unnecessary in this example. Then, the offset cutting path is generated. That is, a clearance is provided at the start point n of the offset line nop to set the approach point m, and the escape point q is set next to the end point p to generate an offset cutting path as indicated by numbers 1 to 4 in FIG. (Step S5).

Then, the process returns to step S2 and it is determined whether or not the offset machining process remains. In this example, since no offset processing remains, the final cutting path generation unit 9 generates a final cutting path that is a cutting path along the work shape. That is, points r and s with clearances are set at the start point a and the end point f of the work shape abcdef, and a final cutting path such as number 4 → 11 shown in FIG. 5 that approaches the point r from the escape point q is generated. (Step S
6). Then, the generated offset cutting path and the final cutting path are stored in the cutting path storage unit 6, and the cutting paths for cutting in the order of numbers 1 → 11 as shown in FIG. 5 are output (step S7), and all processing is performed. finish.

Next, step S4 of the above flow chart.
An example of calculating the intersection point in will be described with reference to the shape example of FIG. In the shape example of FIG. 6, it is determined that the tu portion is to be offset-machined, but since the starting point v of the offset line vw exists in the machining area, a clearance cannot be provided to set the approach point. Then, an orthogonal coordinate axis (xz coordinate axis that is a machine axis) with the starting point v as the origin is obtained, and the coordinate axis closest to the extension line that extends the offset line vw from the starting point v among the coordinate axes, in this example, the positive X coordinate axis. Find the intersection x between the and the material shape. Then, a clearance is provided at the point x to set the approach point y. The cutting path generated in this way is number 1 as shown in FIG.
→ Cutting will be performed in the order of 15. If the coordinate axis closest to the extension line intersects the workpiece shape before intersecting the material shape, the intersection point between the coordinate axis orthogonal to the coordinate axis and the material shape is determined. Then, if any of the coordinate axes intersects with the workpiece shape before intersecting with the material shape, it is determined that processing is impossible and an error is output.

[0011]

As described above, according to the cutting path generating method of the present invention, it is possible to automatically generate the cutting path having the minimum number of passes in accordance with the cutting allowance, so that the program creation time is shortened. The processing efficiency can be significantly improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of functions for realizing a cutting path generation method of the present invention.

FIG. 2 is a flow chart illustrating the method of the present invention.

FIG. 3 shows a first specific example for explaining the method of the present invention.
FIG.

FIG. 4 is a second example showing a specific example for explaining the method of the present invention.
FIG.

FIG. 5 is a third example showing a specific example for explaining the method of the present invention.
FIG.

FIG. 6 is a first diagram showing another specific example for explaining the method of the present invention.

FIG. 7 is a second diagram showing another specific example for explaining the method of the present invention.

FIG. 8 is a block diagram showing an example of functions for realizing a conventional cutting path generation method.

FIG. 9 is a diagram showing a specific example for explaining a conventional method.

[Explanation of symbols]

 7 Offset machining data storage unit 8 Offset cutting path generation unit 9 Final cutting path generation unit

Claims (1)

[Claims] 1. A work path is automatically generated based on input material shape data, work shape data, cutting method data, and offset processing data. And a cutting path generation method, wherein a cutting path along the work shape is automatically generated based on the cutting method data.